unstable


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unstable

(ŭn-stā′bəl)
adj. unsta·bler, unsta·blest
1. Chemistry
a. Decomposing readily.
b. Highly or violently reactive.
2. Physics
a. Decaying with relatively short lifetime. Used of subatomic particles.
b. Radioactive.

un·sta′ble·ness n.
un·sta′bly adv.

unstable

[unstā′bəl]
1 in an excited or active state, such as an atom with a nucleus possessing excess energy.
2 easily broken down or prone to decomposition.

unstable

adjective Referring to the structural or physical lability or instability of a chemical or other substance during production, transportation, or storage. See Unstable reactive substance.

unstable,

adj 1. not firm or fixed in one place; likely to move.
2. capable of undergoing spontaneous change. A nuclide in an unstable state is called
radioactive. An atom in an unstable state is called
excited.
unstable angina
n a form of pain that is prodromal to acute myocardial infarction. It typically has a sudden onset, sudden worsening, and stuttering recurrence over days and weeks. It carries a more severe short-term prognosis than stable chronic angina. Nearly one third of unstable angina patients experience myocardial infarction within 3 months of the first episode.

unstable

having a tendency to disrupt, e.g. unstable chemicals.

unstable fracture
the principal fragments in a reduced fracture are overriding. Slow union or nonunion results.
References in periodicals archive ?
Study the Goodwillie tower of the identity functor of simplicial unstable algebras and relate its layers to AQC.
Unstable shoes were associated with a significant reduction in pain during walking.
Each offers a different kind of unstable surface, allowing the dancer to work up to more challenging situations.
Analysis of key recent licensing and partnership agreements in Unstable Angina Therapeutics market
According to mentioned methodology, first and second order systems were assumed as unstable ones:
The novel unstable balancing simulator of academic rowing has been designed in Engineering Mechanics department of KTU (Kaunas University of Technology, Kaunas, Lithuania) (Fig.
Global Insight has rated the banking system in the country at 55, or very unstable, from 40, which indicates some instability.
Sudan was named as the second most unstable state, due to the continuing crisis in Darfur and the country's growing number of refugees, the report said.
AWALL has partially collapsed - 17 years after Kirklees Council was warned it was unstable.
By Robin Wright WASHINGTON--Iraq now ranks as the world's second most unstable country, ahead of war-ravaged or poverty-stricken nations such as Somalia, Zimbabwe, Ivory Coast, Congo, Afghanistan, Haiti and North Korea, according to the 2007 Failed States Index, issued Monday by the Fund for Peace and Foreign Policy magazine.
This will lower your risk of getting another attack of unstable angina and of having a heart attack.
The test raised fears around the world because the tiny nation is ruled by Kim Jong Il, an unstable dictator (see JS Oct.